--- loncom/homework/cleanxml/post_xml.pm	2016/01/06 16:44:32	1.5
+++ loncom/homework/cleanxml/post_xml.pm	2016/01/14 16:28:06	1.7
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Third step to clean a file.
 #
-# $Id: post_xml.pm,v 1.5 2016/01/06 16:44:32 damieng Exp $
+# $Id: post_xml.pm,v 1.7 2016/01/14 16:28:06 damieng Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -41,6 +41,8 @@ use Cwd 'abs_path';
 use XML::LibXML;
 use HTML::TokeParser; # used to parse sty files
 use Tie::IxHash; # for ordered hashes
+use tth;
+use Apache::html_to_xml;
 
 no warnings 'recursion'; # yes, fix_paragraph is using heavy recursion, I know
 
@@ -50,7 +52,7 @@ my @inline_like_block = ('stringresponse
 my @responses = ('stringresponse','optionresponse','numericalresponse','formularesponse','mathresponse','organicresponse','reactionresponse','customresponse','externalresponse','essayresponse','radiobuttonresponse','matchresponse','rankresponse','imageresponse','functionplotresponse');
 my @block_html = ('html','head','body','section','h1','h2','h3','h4','h5','h6','div','p','ul','ol','li','table','tbody','tr','td','th','dl','dt','dd','pre','noscript','hr','address','blockquote','object','applet','embed','map','form','fieldset','iframe','center','frameset');
 my @no_newline_inside = ('import','parserlib','scriptlib','data','function','label','xlabel','ylabel','tic','text','rectangle','image','title','h1','h2','h3','h4','h5','h6','li','td','p');
-my @preserve_elements = ('script','answer','pre');
+my @preserve_elements = ('script','answer','pre','style');
 my @accepting_style = ('section','h1','h2','h3','h4','h5','h6','div','p','li','td','th','dt','dd','pre','blockquote');
 my @latex_math = ('\alpha', '\theta', '\omicron', '\tau', '\beta', '\vartheta', '\pi', '\upsilon', '\gamma', '\gamma', '\varpi', '\phi', '\delta', '\kappa', '\rho', '\varphi', '\epsilon', '\lambda', '\varrho', '\chi', '\varepsilon', '\mu', '\sigma', '\psi', '\zeta', '\nu', '\varsigma', '\omega', '\eta', '\xi',
   '\Gamma', '\Lambda', '\Sigma', '\Psi', '\Delta', '\Xi', '\Upsilon', '\Omega', '\Theta', '\Pi', '\Phi',
@@ -552,11 +554,11 @@ sub replace_m {
 # Returns the HTML equivalent of LaTeX input, using tth
 sub tth {
   my ($text) = @_;
-  my ($fh, $tmp_path) = tempfile();
-  binmode($fh, ':utf8');
-  print $fh $text;
-  close $fh;
-  my $output = `tth -r -w2 -u -y0 < $tmp_path 2>/dev/null`;
+  my $output = &tth::tth($text);
+  my $errorstring = &tth::ttherror();
+  if ($errorstring) {
+    die $errorstring;
+  }
   # hopefully the temp file will not be removed before this point (otherwise we should use unlink_on_destroy 0)
   $output =~ s/^\s*|\s*$//;
   $output =~ s/<div class="p"><!----><\/div>/<br\/>/; # why is tth using such ugly markup for \newline ?
@@ -567,7 +569,7 @@ sub tth {
 sub html_to_dom {
   my ($text) = @_;
   $text = '<root>'.$text.'</root>';
-  my $textref = html_to_xml::html_to_xml(\$text);
+  my $textref = Apache::html_to_xml::html_to_xml(\$text);
   utf8::upgrade($$textref); # otherwise the XML parser fails when the HTML parser turns &nbsp; into a character
   my $dom_doc = XML::LibXML->load_xml(string => $textref);
   my $root = $dom_doc->documentElement;
@@ -2394,8 +2396,29 @@ sub pretty {
   my $type = $node->nodeType;
   if ($type == XML_ELEMENT_NODE) {
     my $name = $node->nodeName;
-    if ((string_in_array($all_block, $name) || string_in_array(\@inline_like_block, $name)) &&
-        !string_in_array(\@preserve_elements, $name)) {
+    if (string_in_array(\@preserve_elements, $name)) {
+      # remove newlines at the beginning and the end of preserve elements
+      if (defined $node->firstChild && ($node->firstChild->nodeType == XML_TEXT_NODE ||
+          $node->firstChild->nodeType == XML_CDATA_SECTION_NODE)) {
+        my $text = $node->firstChild->nodeValue;
+        $text =~ s/^\n+//;
+        if ($text eq '') {
+          $node->removeChild($node->firstChild);
+        } else {
+          $node->firstChild->setData($text);
+        }
+      }
+      if (defined $node->lastChild && ($node->lastChild->nodeType == XML_TEXT_NODE ||
+          $node->lastChild->nodeType == XML_CDATA_SECTION_NODE)) {
+        my $text = $node->lastChild->nodeValue;
+        $text =~ s/\n+$//;
+        if ($text eq '') {
+          $node->removeChild($node->lastChild);
+        } else {
+          $node->lastChild->setData($text);
+        }
+      }
+    } elsif (string_in_array($all_block, $name) || string_in_array(\@inline_like_block, $name)) {
       # make sure there is a newline at the beginning and at the end if there is anything inside
       if (defined $node->firstChild && !string_in_array(\@no_newline_inside, $name)) {
         my $first = $node->firstChild;
@@ -2478,26 +2501,6 @@ sub pretty {
         if ($text eq '') {
           $node->removeChild($node->lastChild);
         } else {
-          $node->lastChild->setData($text);
-        }
-      }
-    } elsif (string_in_array(\@preserve_elements, $name)) {
-      # collapse newlines at the beginning and the end of scripts
-      if (defined $node->firstChild && $node->firstChild->nodeType == XML_TEXT_NODE) {
-        my $text = $node->firstChild->nodeValue;
-        $text =~ s/^\n( *\n)+/\n/;
-        if ($text eq '') {
-          $node->removeChild($node->firstChild);
-        } else {
-          $node->firstChild->setData($text);
-        }
-      }
-      if (defined $node->lastChild && $node->lastChild->nodeType == XML_TEXT_NODE) {
-        my $text = $node->lastChild->nodeValue;
-        $text =~ s/\n( *\n)+$/\n/;
-        if ($text eq '') {
-          $node->removeChild($node->lastChild);
-        } else {
           $node->lastChild->setData($text);
         }
       }